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1.
Cureus ; 11(3): e4179, 2019 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31106079

RESUMO

Acquired hemophilia B is a rare bleeding disorder in which circulating specific antibodies inhibit the coagulation factors. Usually, it is associated with autoimmune diseases, malignancy and some infections such as hepatitis B (HBV) and C (HCV) viruses. The association with the human immunodeficiency virus (HIV) is rare. We present the first case of hemophilia B acquired in a patient with HIV. A 36-year-old woman with a history of HIV infection stage 3 acquired immunodeficiency syndrome (AIDS) (CDC 2014) and glomerulopathy secondary to HIV. She consulted for subacute non-dysenteric diarrhea. During her hospitalization, bacteremia by methicillin-sensitive Staphylococcus aureus (S.aureus) was documented, requiring hemodialysis catheter replacement with profuse bleeding during the procedure. The coagulation tests showed prolonged activated partial thromboplastin time (aPTT), normal prothrombin time (PT), mixing test with Rosner index: 8.8%, negative lupus anticoagulant, and specific tests for normal factor VIII and XI. The activity of factor IX was <50% and the inhibitor was increased, which confirms the diagnosis of hemophilia B. Acquired hemophilia B in a patient with HIV infection is not a frequent association; it should be suspected in the context of bleeding with prolonged aPTT.

2.
Pulm Med ; 2012: 736290, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22848818

RESUMO

Ultrafine particles (UFPs) contribute to health risks associated with air pollution, especially respiratory disease in children. Nonetheless, experimental data on UFP deposition in asthmatic children has been minimal. In this study, the effect of ventilation, developing respiratory physiology, and asthmatic condition on the deposition efficiency of ultrafine particles in children was explored. Deposited fractions of UFP (10-200 nm) were determined in 9 asthmatic children, 8 nonasthmatic children, and 5 nonasthmatic adults. Deposition efficiencies in adults served as reference of fully developed respiratory physiologies. A validated deposition model was employed as an auxiliary tool to assess the independent effect of varying ventilation on deposition. Asthmatic conditions were confirmed via pre-and post-bronchodilator spirometry. Subjects were exposed to a hygroscopic aerosol with number geometric mean diameter of 27-31 nm, geometric standard deviation of 1.8-2.0, and concentration of 1.2 × 10(6) particles cm(-3). Exposure was through a silicone mouthpiece. Total deposited fraction (TDF) and normalized deposition rate were 50% and 32% higher in children than in adults. Accounting for tidal volume and age variation, TDF was 21% higher in asthmatic than in non-asthmatic children. The higher health risks of air pollution exposure observed in children and asthmatics might be augmented by their susceptibility to higher dosages of UFP.

3.
Sci Total Environ ; 425: 27-34, 2012 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-22464030

RESUMO

The use of land-use regression (LUR) techniques for modeling small-scale variations of intraurban air pollution has been increasing in the last decade. The most appealing feature of LUR techniques is the economical monitoring requirements. In this study, principal component analysis (PCA) was employed to optimize an LUR model for PM2.5. The PM2.5 monitoring network consisted of 13 sites, which constrained the regression model to a maximum of one independent variable. An optimized surrogate of vehicle emissions was produced by PCA and employed as the predictor variable in the model. The vehicle emissions surrogate consisted of a linear combination of several traffic variables (e.g., vehicle miles traveled, speed, traffic demand, road length, and time) obtained from a road network used for traffic modeling. The vehicle-emissions surrogate produced by the PCA had a predictive capacity greater (R2=.458) than the traffic variable, Traffic Demand summarized for a 1 km buffer, with best predictive capacity (R2=.341). The PCA-based method employed in this study was effective at increasing the fit of an ordinary LUR model by optimizing the utilization of a PM2.5 dataset from small-n monitoring network. In general, the method used can contribute to LUR techniques in two major ways: 1) by improving the predictive power of the input variable, by substituting a principal component for a single variable and 2) by creating an orthogonal set of predictor variables, and thus fulfilling the no colinearity assumption of the linear regression methods. The proposed PCA method, should be universally applicable to LUR methods and will expand their economical attractiveness.


Assuntos
Poluição do Ar/análise , Modelos Teóricos , Análise de Componente Principal , Emissões de Veículos , Exposição Ambiental , Monitoramento Ambiental/métodos , Análise de Regressão , Texas
4.
J Blood Med ; 1: 71-8, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-22282686

RESUMO

In the US the dominant sources of lead through much of the 20th Century (eg, vehicular emissions, plumbing, household paint) have been significantly diminished. The reductions in adult and pediatric average blood lead levels in the US have been extraordinary. Progress continues: the US Environmental Protection Agency recently developed a new air standard for lead. In the 21st Century, the average blood lead level in a society may be seen as a marker of the status of their public's health. However, the threat of lead exposure remains a significant public health problem among subpopulation groups in the US and in many less developed countries. This paper examines some of the specific issues involved in the reduction of blood lead in a post-industrial era. These involve the control of the remaining exogenous primary sources, both general (eg, industrial emissions) and specific (eg, at-risk occupations), exogenous secondary sources (eg, contaminated urban soils, legacy lead-based paints), an endogenous source (ie, cumulative body lead burden) and emergent sources.

5.
Toxicol Appl Pharmacol ; 238(1): 1-10, 2009 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-19410595

RESUMO

Particulate matter less than 10 microm (PM10) has been shown to be associated with aggravation of asthma and respiratory and cardiopulmonary morbidity. There is also great interest in the potential health effects of PM2.5. Particulate matter (PM) varies in composition both spatially and temporally depending on the source, location and seasonal condition. El Paso County which lies in the Paso del Norte airshed is a unique location to study ambient air pollution due to three major points: the geological land formation, the relatively large population and the various sources of PM. In this study, dichotomous filters were collected from various sites in El Paso County every 7 days for a period of 1 year. The sampling sites were both distant and near border crossings, which are near heavily populated areas with high traffic volume. Fine (PM2.5) and Coarse (PM10-2.5) PM filter samples were extracted using dichloromethane and were assessed for biologic activity and polycyclic aromatic (PAH) content. Three sets of marker genes human BEAS2B bronchial epithelial cells were utilized to assess the effects of airborne PAHs on biologic activities associated with specific biological pathways associated with airway diseases. These pathways included in inflammatory cytokine production (IL-6, IL-8), oxidative stress (HMOX-1, NQO-1, ALDH3A1, AKR1C1), and aryl hydrocarbon receptor (AhR)-dependent signaling (CYP1A1). Results demonstrated interesting temporal and spatial patterns of gene induction for all pathways, particularly those associated with oxidative stress, and significant differences in the PAHs detected in the PM10-2.5 and PM2.5 fractions. Temporally, the greatest effects on gene induction were observed in winter months, which appeared to correlate with inversions that are common in the air basin. Spatially, the greatest gene expression increases were seen in extracts collected from the central most areas of El Paso which are also closest to highways and border crossings.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Exposição Ambiental/efeitos adversos , Material Particulado/efeitos adversos , Hidrocarbonetos Policíclicos Aromáticos/efeitos adversos , Brônquios/citologia , Brônquios/efeitos dos fármacos , Linhagem Celular , Citocromo P-450 CYP1A1/efeitos dos fármacos , Citocromo P-450 CYP1A1/metabolismo , Citocinas/efeitos dos fármacos , Citocinas/metabolismo , Monitoramento Ambiental/métodos , Células Epiteliais/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Pulmão/citologia , Pulmão/efeitos dos fármacos , México , Estresse Oxidativo/efeitos dos fármacos , Tamanho da Partícula , Estações do Ano , Texas
6.
PLoS One ; 4(4): e5019, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19340295

RESUMO

BACKGROUND: Despite the dramatic decrease in airborne lead over the past three decades, there are calls for regulatory limits on this potent pediatric neurotoxin lower even than the new (2008) US Environmental Protection Agency standard. To achieve further decreases in airborne lead, what sources would need to be decreased and what costs would ensue? Our aim was to identify and, if possible, quantify the major species (compounds) of lead in recent ambient airborne particulate matter collected in El Paso, TX, USA. METHODOLOGY/PRINCIPAL FINDINGS: We used synchrotron-based XAFS (x-ray absorption fine structure) to identify and quantify the major Pb species. XAFS provides molecular-level structural information about a specific element in a bulk sample. Pb-humate is the dominant form of lead in contemporary El Paso air. Pb-humate is a stable, sorbed complex produced exclusively in the humus fraction of Pb-contaminated soils; it also is the major lead species in El Paso soils. Thus such soil must be the dominant source, and its resuspension into the air, the transfer process, providing lead particles to the local air. CONCLUSIONS/SIGNIFICANCE: Current industrial and commercial activity apparently is not a major source of airborne lead in El Paso, and presumably other locales that have eliminated such traditional sources as leaded gasoline. Instead, local contaminated soil, legacy of earlier anthropogenic Pb releases, serves as a long-term reservoir that gradually leaks particulate lead to the atmosphere. Given the difficulty and expense of large-scale soil remediation or removal, fugitive soil likely constrains a lower limit for airborne lead levels in many urban settings.


Assuntos
Poluentes Atmosféricos/análise , Chumbo/análise , Poluentes do Solo/análise , Análise Espectral/métodos , Análise de Fourier , Análise dos Mínimos Quadrados , Raios X
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